The
image is of the Keenan system of colliding
galaxies and was collected during an Astronomer Night program
at the observatory by Adam Block, who is also the Observing Programs
Coordinator at the SkyCenter.

"A
fascinating aspect to this image is that it resembles the outcome of a
computer simulation designed to demonstrate the result of galactic
collisions," Block said.

"Long ago I was inspired by the work of
John Dubinski and others on what are called galactic mergers. Dubinski
created code that ran on a supercomputer to simulate the merger of the
Milky Way, where we live, and our nearest large neighbor, the Andromeda
Galaxy, to create Milkomeda," Block said.

The movie that
Dubinski made, part of his GRAVITAS series, has
been a part of the Mount Lemmon SkyCenter's program for several years.

Block said, "There is a point in the simulation where the resulting
pattern looks – to my eye – very similar to NGC 5216, the Keenan
system."

"Assuming that the physics are correct, it is
remarkable that the universe is large enough to express examples of all
potential possibilities. This lends credence to the idea that
astrophysical computer simulations may be predictive," he said.

Block
said the tidal stream that seems to connect the galaxies with their
two counter-oriented tidal tails is represented well in the comparison.

The pattern, he said, exists only briefly in the full simulation.

The Mount Lemmon SkyCenter offers a number of public programs run
from the observatory at the highest point in the Santa Catalina
Mountains.